What are ArgoCD Sync Waves and Hooks?

Question

Accepted Answer

**Sync Waves** — deployment order (wave -1 → 0 → 1 → 2). **Hooks** — actions before/after synchronization.

**Sync Waves:**
```yaml
# Namespace (wave -1)
apiVersion: v1
kind: Namespace
metadata:
  name: production
  annotations:
    argocd.argoproj.io/sync-wave: "-1"
---
# Deployment (wave 1)
apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
  annotations:
    argocd.argoproj.io/sync-wave: "1"
---
# Ingress (wave 3)
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: myapp
  annotations:
    argocd.argoproj.io/sync-wave: "3"
```

**Hooks (PreSync — DB migration):**
```yaml
apiVersion: batch/v1
kind: Job
metadata:
  name: db-migrate
  annotations:
    argocd.argoproj.io/hook: PreSync
    argocd.argoproj.io/hook-delete-policy: HookSucceeded
spec:
  template:
    spec:
      containers:
        - name: migrate
          image: myapp:latest
          command: ["python", "migrate.py"]
      restartPolicy: Never
  backoffLimit: 1
```

**Hook types:** PreSync, Sync, PostSync, SyncFail, Skip.

DevOps: What are ArgoCD Sync Waves and Hooks?